Fixed international fees are a problem because there are places like the Ukraine where an Aikido seminar might cost $1/day, and like 200 people will show up to pay, and another 100 people will show up to watch because they can't afford it. Charge them $10/year for a membership fee and people have to quit.

A long time ago, I heard that Yamada sensei's dojo adjusted the monthly fee to be proportional to the fee of the subway. So if it cost 80 cents to ride the subway, they charged $80/month to train aikido. When it went up to $1.25 to ride the subway, they went up to $125/month. I have no idea if this is accurate, but I like the concept.